{ "data": { "question": { "questionId": "3450", "questionFrontendId": "3178", "boundTopicId": null, "title": "Find the Child Who Has the Ball After K Seconds", "titleSlug": "find-the-child-who-has-the-ball-after-k-seconds", "content": "

You are given two positive integers n and k. There are n children numbered from 0 to n - 1 standing in a queue in order from left to right.

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Initially, child 0 holds a ball and the direction of passing the ball is towards the right direction. After each second, the child holding the ball passes it to the child next to them. Once the ball reaches either end of the line, i.e. child 0 or child n - 1, the direction of passing is reversed.

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Return the number of the child who receives the ball after k seconds.

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Example 1:

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Input: n = 3, k = 5

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Output: 1

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Explanation:

\n\n\n\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\n
Time elapsedChildren
0[0, 1, 2]
1[0, 1, 2]
2[0, 1, 2]
3[0, 1, 2]
4[0, 1, 2]
5[0, 1, 2]
\n
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Example 2:

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Input: n = 5, k = 6

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Output: 2

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Explanation:

\n\n\n\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\n
Time elapsedChildren
0[0, 1, 2, 3, 4]
1[0, 1, 2, 3, 4]
2[0, 1, 2, 3, 4]
3[0, 1, 2, 3, 4]
4[0, 1, 2, 3, 4]
5[0, 1, 2, 3, 4]
6[0, 1, 2, 3, 4]
\n
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Example 3:

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Input: n = 4, k = 2

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Output: 2

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Explanation:

\n\n\n\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\n\t\n
Time elapsedChildren
0[0, 1, 2, 3]
1[0, 1, 2, 3]
2[0, 1, 2, 3]
\n
\n\n

 

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Constraints:

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Compiled with clang 17 using the latest C++ 20 standard, and libstdc++ provided by GCC 11.

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Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 21. Using compile arguments: --enable-preview --release 21

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Most standard library headers are already included automatically for your convenience.

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Includes Pair class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.

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Python 2.7.12.

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Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.

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Compiled with gcc 11 using the gnu11 standard.

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Most standard library headers are already included automatically for your convenience.

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3. Deleting an item in a hash:\\r\\n

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C# 12 with .NET 8 runtime

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Node.js 20.10.0.

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Ruby 3.2

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Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms

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Swift 5.9.

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Go 1.21

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Python 3.11.

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Scala 3.3.1.

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Kotlin 1.9.0.

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Rust 1.74.1. Your code will be compiled with opt-level 2.

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PHP 8.2.

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With bcmath module

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TypeScript 5.1.6, Node.js 20.10.0.

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Racket CS v8.11

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Using #lang racket

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Required data/gvector data/queue data/order data/heap automatically for your convenience

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Your code will be run directly without compiling

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